1. Field of the Invention
The present invention is to a system for conveying packaging cushions to multiple packing stations. More particularly, the present invention is to a system that automatically and efficiently produces and delivers, monitors and replenishes a string of packaging cushions through an elongated duct into storage bins located above multiple packing stations.
2. Description of Related Art
When articles are packaged in a container or box for shipping, there are usually void spaces in the container. Protective packaging material for articles of different sizes and shapes is commonly used to cushion articles during shipping. Numerous types and forms of packaging material for this purpose have been used including waste paper, embossed paper, laminated bubble paper, foamed material and plastic beads. These packaging materials do not always provide the cushioning and void fill most effect to protect articles during shipment. Also, these packaging materials can be costly and often require that a significant amount of labor be performed at the packing station. As a result, thermoplastic cushions have been proposed for use in protecting articles during shipment. One such packaging cushion that has found widespread use is a multiple use inflatable cushion that is specifically designed to be placed around a particular article to be protected and is inflated after the cushion is placed in the shipping container. These types of cushions, while expensive, are particularly useful for the protection of certain types of articles but because each cushion is inflated at the packaging station the packaging process is labor intensive.
However, advantages may be obtained by using simple cellular cushions made of thermoplastic material. Examples of methods of making such cellular cushions are shown in U.S. Pat. Nos. 3,817,803 and 5,340,632. The ability to make these types of cushions simply and at the point of use is of paramount importance. Another example of a device for making cushions is U.S. Pat. No. 5,942,076 that describes a machine that includes sealing sheets of thermoplastic material together to form a tube, introducing air to the tubular material and sealing the ends to make rectangular air-filled cushions of various sizes. The cushion supply machine is located adjacent the product conveyer so that as a container, such as a corrugated box, holding an article to be protected, passes the cushion forming section the operator starts the machine and a series of inflated packaging cushions fall into the container. This system supplies only one packing station at a time.
Once a string of packaging cushions has been formed it is necessary to deliver them to the article packing station. U.S. Pat No. 6,536,183 discloses a system for delivering packaging cushions to a point of use in which a continuous string of the cushions is fed into a elongated duct with the string extending longitudinally of the duct. An air flow is established in the duct to convey the string of cushions through the duct to the point of use. In U.S. Pat. No. 6,428,246 there is disclosed a system and method for making, conveying and dispensing packing material to a packing station. The packaging material is a chain of linked cushions and the system includes a pressurized duct to an elongated hopper located above a plurality of packing stations. The elongated hopper includes air jets that transfer the string of packaging cushions between each jet to a remote end of the hopper. Located at intervals along the length of the hopper are a series of dispensing openings so the cushions may be accessed ax each of the packing stations.
Thus, it is desirable to provide a system capable of efficiently and automatically supplying a string of packaging cushions to be stored in a hopper or bin located at each of multiple packing stations.